Single customer view is a capability enhancement in External Contacts. It allows different identifiers, such as email address, phone number, web ID, to be associated under the one contact record and links conversations across channels in Genesys Cloud. 

Single customer view puts empathy into action and your contacts at the center of their experiences with your organization. Relying on identity resolution and customer journeys, single customer view enables agents to provide personal service with a view to each contact’s complete story.